As integrated circuit device scaling continues, current levels consumed by a device such as a processor continue to increase due to a number of factors including: an increase in the number of transistors per unit area on a die; introduction of new performance features; an increase in the number of cores in a processor; and reduction in supply voltage while the power envelope remains constant.
Among the deleterious impacts of increased current are the need to design a higher power voltage regulator and system power supply, the need for higher voltage to compensate for IR droop, an increase in the number of capacitors required and the need for better voltage regulators to supply higher current with faster feedback mechanisms. Guard banding is a technique that compensates for expected maximum current (Icc), degradation caused by factors such as excess current, and may involve degrading threshold voltage or increasing operating voltage (VDD), among other things. However, these mechanisms can lead to increased power consumption.